1. Field of the Invention
The present invention relates generally to connectors and contact members, and more particularly to a connector that allows an end part of an object to be connected to be inserted into and connected to the connector and to a contact member employed in the connector. The connector may be a card edge connector that is used in a server or RAID apparatus and allows an end part of a circuit board to be inserted into and connected to the connector.
2. Description of the Related Art
Inside apparatuses, multiple card edge connectors are arranged and mounted on a motherboard, and circuit boards such as DIMMs (Dual In-line Memory Modules) are inserted into and connected to corresponding card edge connectors so as to be arranged in a vertical position with respect to the motherboard. Here, the card edge connector is required to establish a highly reliable electrical connection with the circuit board.
In general, dirt or dust adhering to pads of the circuit board is the main cause of poor connections. Therefore, the card edge connector is required to establish a highly reliable electrical connection by cleaning the pads of the circuit board in such a manner as to rub the adhering dirt or dust away from the pads of the circuit board so that contact parts are pressed into contact with the cleaned parts.
For example, Japanese Laid-Open Patent Application No. 11-233183 and Japanese Laid-Open Patent Application No. 2001-126791 show conventional card edge connectors that intend to establish a reliable electrical connection with a cleaning function.
The card edge connector described in Japanese Laid-Open Patent Application No. 11-233183includes a contact member having two parts bent in a corrugated manner so as to have a first contact part and a second contact part arranged from the end side. The first contact part rubs dirt or dust away from a corresponding pad of the circuit board, and the second contact part comes into contact with the cleaned pad.
The card edge connector described in Japanese Laid-Open Patent Application No. 2001-126791 has a contact member divided into right and left lead parts by a slit extending in the longitudinal directions of the contact member so that a first contact part is formed on the left lead part and a second contact part is formed on the right lead part. The first contact part rubs dirt or dust away from a corresponding pad of the circuit board, and the second contact part comes into contact with the cleaned pad.
However, according to the card edge connector described in Japanese Laid-Open Patent Application No. 11-233183, if the first contact part deforms, the second contact part also deforms following the deformation of the first contact part. Thus, there is no independency between the first contact part and the second contact part. As a result, in particular, the contact pressure of the second contact part with the pad is subject to the deformation of the first contact part to become lower than an intended value, so that the reliability of electrical connection is reduced.
According to the card edge connector described in Japanese Laid-Open Patent Application No. 2001-126791, the independency between the first contact part and the second contact part is better than that of the configuration described in Japanese Laid-Open Patent Application No. 11-233183. However, the base of the right lead part and the base of the left lead part are extremely close to each other with only a slit therebetween. Accordingly, in some cases, a warp at the base of the left lead part may be transmitted to the base of the right lead part. Thus, there is not sufficient independency between the first contact part and the second contact part, so that the contact pressure of the second contact part with the pad may become lower than an intended value.
Further, there is a problem in that the card edge connector described in Japanese Laid-Open Patent Application No. 2001-126791 is difficult to use for currently used circuit boards. That is, the pad pitch is as narrow as approximately 1 mm in current circuit boards. However, this card edge connector has the right lead part and the left lead part arranged in its longitudinal directions, which prevents this card edge connector from accommodating narrow pad pitches of current circuit boards.